There is a growing demand for lighter weight, ergonomic utility tools, such as crimping and cutting tools, to reduce operator injury. Of particular interest is the need for lighter weight tools that are used by utility workers. Much of the work performed by utility workers is performed while standing within the bucket of a bucket truck. The nature of the work often requires the workers to hold a crimp tool in position on an electrical connector with their arms extended. The utility tools are generally heavy and awkward to operate. With rising concerns regarding preventing personal injury while operating such equipment, ergonomics are an important consideration. The weight of the utility tool becomes critical, as does the crimp cycle times.
Crimping and cutting tool designs vary in size, weight and configuration. Although most utility tools are high pressure (10,000 psi), low pressure (1500-3000 psi) utility tools are also used when working from the bucket of the bucket truck.
Low pressure crimp tools can be heavy and very unbalanced. However, in most cases, low pressure crimp tools crimp quickly. These low pressure crimp tools are typically powered by a hydraulic pump source, such as directly from the bucket truck. Low pressure operated crimp tools traditionally incorporate a large piston that is subjected to 1500-3000 psi operating pressure. The disadvantage of these tools is that they are heavy, big and not well balanced. From an ergonomic point of view, they score very low.
High pressure crimp tools are relatively light weight and ergonomic, however, they crimp slowly. These tools may also require gripping in an area of high pressure, which can be dangerous if there is a failure.
High pressure crimp tools are usually operated with an intensifier or a booster pump, which is powered by a bucket truck circuit. The booster or intensifier operates on low pressure and increases or intensifies the output to the 10,000 psi operating pressure requirement for high pressure tools. The booster pump may incorporate a hydraulic motor, such as gerotor or gear motor type, which can drive a high pressure pump to deliver 10,000 psi oil to a remote crimp head via a hydraulic hose. These units tend to be very slow during the high pressure delivery cycle as a result of low volumetric flow rates. There are also intensifiers that have reciprocating pistons that incorporate shuttle spools to sequence the pistons. These units are slow and have many moving parts.
Accordingly, a need exists for an improved high pressure tool that is easily handled and operates quickly.